How to tell if a networking board is telecom or peripheral? Is there a general guideline? I have attached couple switch/router large/medium size boards as samples.

What determines a board grade here is the density of IC chips on the board itself. In looking through the ten you have, boards 5 and 10 would be peripheral grade given the amount of IC chips compared to the board size. Everything else is telecom grade.

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kgryczan
Forum Moderator

5 may get telco as well. I've sold a few to board sort and have had them go both ways.
Those have heavy thick silver plate on both sides.
Looks like a catalyst.
I'm pulling from the air here but i am figuring that it's the card ports that make or break telco.
My double stacks (4 ports in two stacks) alwas got telco and the single stacks always got peripheral.
So counting the levels in the card ports on the front left. If each slot has two rows then its a single stack... go peripheral
If there's four rows in each port slot go telco.

As an alternative if I'm right and it's a catalyst board and you're good with a soldering iron...!
Remove the two express card sockets and take the hit with going peripheral.
The pins on catalyst boards are all GOLD MILLED not flash plated. Better than military grade.
My scan tests have consistently shown them to be 1/20th 18k milled. Same as designer fashion jewelry. I can't promise you that but history shows the risk to be worth it.

1/20x18 is $1.40 per gram at time of posting this (at a 22% spot reduction)
So you're looking at real value for those pins.